Disc player and method of reproducing information on disc

ABSTRACT

A disc player reproduces information in a plurality of blocks sequentially provided on a disc. The disc player includes an optical pickup reading the information recorded on the disc; an optical-pickup moving unit moving the optical pickup; and a controller controlling the optical pickup moving unit. When the optical pickup is not able to read the information recorded on the disc, the controller controls the moving unit to move the optical pickup to the head of a block subsequent to the block where the optical pickup cannot read the information if the block to which the optical pickup reaches in a predetermined time is different from the block where the optical pickup cannot read the information recorded on the disc.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a disc player reproducing music orvideo information recorded on a disc and a method of reproducing musicor video information recorded on a disc.

2. Description of the Related Art

Disc players that reproduce information on discs (for example, opticaldiscs) having content, such as music information or video information,recorded thereon generally perform signal processing, such as errorcorrection, for signals read by optical pickups while performingtracking in which the optical pickups follow the recording tracks on therotating discs in order to reproduce the content.

Although read errors can occur because of scratches, etc. on therecording tracks, it is possible to restore minor errors by the errorcorrection.

However, if deep scratches that cannot be restored by the errorcorrection are made on the recording tracks, a tracking servo causingthe optical pickups to follow the recording tracks does not operatenormally, possibly causing a so-called locked loop, in which the samepositions are repeatedly traced on the recording tracks.

In order to avoid such a locked loop, a technology of detecting ascratch on a recording track from a reduction in the level of a signalread from an optical pickup and jumping part of the recording track ifthe scratch is detected on the recording track is disclosed in JapaneseUnexamined Patent Application Publication No. 7-98871 (Patent Document1).

Another technology in a disc player is disclosed in Japanese UnexaminedPatent Application Publication No. 11-328686 (Patent Document 2). Withthis technology, when the current position of an optical pickup is movedbackward because of a scratch on the disc (when it is determined thatthe optical pickup moves toward the inner side of the disc where therecording track runs from the inner side of the disc to the outer sidethereof), the optical pickup is caused to perform a track jump whileincreasing the number of tracks such that the optical pickup movestoward the outer side of the disc. When the number of track jumpsexceeds a predetermined number of times, the optical pickup is forcedlyfed toward the outer side of the disc for a predetermined time tocontinue the reproduction of information on the disc.

When a scratch or the like is made on the disc, the optical pickup ismoved so as to jump part of the recording track in the technologydisclosed in Patent Document 1, and the optical pickup is forcedly movedfor the predetermined time in the technology disclosed in PatentDocument 2. Accordingly, the optical pickup can be moved across musictracks, which are formed by dividing music information recorded on thedisc for every tune, or across chapters, which are formed by dividingvideo information recorded on the disc for every predetermined unit.Since moving the optical pickup in these manners inhibits reproductionof the head of the destination tune or chapter, there is a problem inthat even a tune or chapter having no scratch is reproduced with thehead of the tune or chapter being skipped, thus hindering a user fromcomfortably listening to or watching the music information or videoinformation.

SUMMARY OF THE INVENTION

In order to resolve the above problem, it is desirable to reproduce thehead of a block, such as a tune or a chapter, as much as possible whenthe information on a disc having a scratched portion is reproduced withthe scratched portion being skipped.

According to an embodiment, the present invention provides a disc playerthat reproduces information in a plurality of blocks sequentiallyprovided on a disc. The disc player includes an optical pickup operableto read the information recorded on a first block of the disc; a movingunit operable to move the optical pickup for a predetermined period oftime when the optical pickup is no longer able to read the informationrecorded on the first block; and a controller operable to direct themoving unit to move the optical pickup to the head of a second blocksubsequent to the first block if the portion of the disc to which theoptical pickup will reach after being moved for the predetermined timeis within the second block.

According to another embodiment, the present invention provides a methodof reproducing information in a plurality of blocks sequentiallyprovided on a disc. The method includes determining a position where anoptical pickup will reach in a predetermined time when the opticalpickup is not able to read the information recorded on a first block ofthe disc; determining whether the position is beyond the head of asecond block subsequent to the first block; and moving the opticalpickup to the head of the second block if it is determined that theposition is beyond the head of the second block.

According to another embodiment, the present invention provides a methodof reproducing information in a plurality of blocks sequentiallyprovided on a disc. The method includes moving an optical pickup by adistance corresponding to a predetermined time when the optical pickupis not able to read the information recorded on a unreadable portion ofthe disc; determining whether the block to which the optical pickup hasbeen moved to includes the unreadable portion of the disc; and movingthe optical pickup to the head of a the block to which the opticalpickup has been moved if it is determined that the block does notinclude the unreadable portion of the disc.

According to the embodiments of the present invention, since the opticalpickup is moved to the head of the destination block to continue thereproduction of the information when the destination block to which theoptical pickup is moved so as to skip a scratched portion is differentfrom the block before the movement, the entire block having no scratchcan be reproduced. Accordingly, a user can comfortably listen to orwatch the information even on the disc having a scratched portion.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing an example of the structure of a discplayer according to first and second embodiments;

FIG. 2 shows an example of the data structure of a subcode;

FIG. 3 shows an example of the data structure of a TOC;

FIGS. 4A to 4C show an example of the method of reproducing informationon the disc in the disc player according to the first embodiment;

FIG. 5 is a flowchart showing the operation of the disc player and themethod of reproducing the information on the optical disc in the discplayer, according to the first embodiment;

FIGS. 6A to 6C show an example of the method of reproducing informationon the disc in the disc player according to the second embodiment;

FIG. 7 is a flowchart showing the operation of the disc player and themethod of reproducing the information on the optical disc in the discplayer, according to the second embodiment;

FIGS. 8A and 8B show a modified example of the method of reproducing theinformation on the disc in the disc player according to the firstembodiment; and

FIGS. 8A to 9D′ show an example of the method of reproducing theinformation on the disc when a scratch is made at the destination of theoptical pickup in the disc player according to the first and secondembodiments.

FIGS. 9A to 9D′ show an example of the method of reproducing theinformation on the disc when a scratch is made at the destination of theoptical pickup in the disc player according to the first and secondembodiments.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

First Embodiment

A first embodiment of the present invention will be described below withreference to the attached drawings. FIG. 1 is a block diagram showing anexample of the structure of a disc player 1 according to the firstembodiment. Referring to FIG. 1, an optical disc 10 (for example, acompact disc (CD)) has a scratch on the signal recording surface havinginformation recorded thereon. The information recorded on the opticaldisc 10 includes music information and subcodes. The music informationrecoded on the optical disc 10 is composed of a plurality of musictracks (for example, tunes). The plurality of music tracks haverespective music track numbers. The plurality of music tracks arerecorded on a spiral recording track running from the inner side of theoptical disc 10 to the outer side thereof in the order of the musictrack numbers. A lead-in area is provided at the most inner side and alead-out area is provided at the most outer side. The music trackscorrespond to blocks described in the claims.

The recording track has subcodes recorded thereon, in addition to theplurality of music tracks. The subcodes have eight types P, Q, R, S, T,U, V, and W. Among these types of subcodes, the P subcode is used forlocating the start of a tune, the Q subcode is used for time data of thetune, and the remaining subcodes R to W are used for other data. Onesubcode is composed of data corresponding to one second.

Each subcode has the data structure, for example, shown in FIG. 2.Referring to FIG. 2, “Music track number TNO” indicates the music tracknumber of a position where the subcode is recorded and is set to anyvalue of “00” to “99” and “AA”. The values “01” to “99” denote thenumbers of music tracks on which music information is actually recorded.The music track is the lead-in area when the music track number TNO hasa value of “00”, and the music track is the lead-out area when the musictrack number TNO has a value of “AA”. “Index” indicates the index of aposition where the subcode is recorded and is set to any value of “00”to “99”. Segmentation of the music track forms the indexes. “MIN(Minute)”, “SEC (Second)”, and “FRAME (Frame number)” indicate valuesrepresenting the elapsed time during which the tune advances from thehead of the tune (music track) to the position where the subcode isrecorded. “ZERO” has a value of “0”, which is represented as “00000000”in eight bits.

“AMIN”, “ASEC”, and “AFRAME” indicate values representing the absolutetime during which the tune advances from the head (excluding the lead-inarea) of the optical disc 10 to the position where the subcode isrecorded. The “AMIN” has any value of “0” to “74” and the “ASEC” has anyvalue of “0” to “59” because the maximum recording time on the opticaldisc 10 is 74 minutes. The “AFRAME” has any value of “0” to “74” and 75frames corresponds to one second.

The lead-in area of the optical disc 10 has a table of contents (TOC) ofthe music information recorded on the optical disc 10.

The TOC has the data structure, for example, as shown in FIG. 3.Referring to FIG. 3, “Music track number TNO” indicates a music tracknumber of a position where the TOC is recorded. Since the TOC isrecorded in the lead-in area, the “Music track number TNO” has a valueof “00”. “POINT” indicates a music track number on the optical disc 10and has any value of “00” to “99”, “A0”, “A1”, and “A2”. “MIN (Minute)”,“SEC (Second)”, and “FRAME (Frame number)” indicate values representingthe elapsed time during which the tune advances from the head of thetune (music track) to the position where the TOC is recorded. “ZERO” hasa value of “0”, which is represented as “00000000” in eight bits.

“PMIN”, “PSEC”, and “PFRAME” have different meanings depending on thevalue of the “POINT”. When the “POINT” has any value of “00” to “99”,the “PMIN”, “PSEC”, and “PFRAME” indicate values representing theabsolute time during which the tune advances from the head (excludingthe lead-in area) of the optical disc 10 to the head of the music trackindicated by the value in the “POINT”. The “PMIN” has any value of “0”to “74” and the “PSEC” has any value of “0” to “59”. The “PFRAME” hasany value of “0” to “74”.

When the “POINT” has a value of “A0”, the “IPMIN” indicates the firstmusic track number on the optical disc 10, and both the “PSEC” and“PFRAME” have a value of “0”. When the “POINT” has a value of “A1”, the“PMIN” indicates the last music track number on the optical disc 10, andboth the “PSEC” and “PFRAME” has a value of “0”. When the “POINT” has avalue of “A2”, the “PMIN”, “PSEC”, and “PFRAME” indicate valuesrepresenting the absolute time when the lead-out area starts.

Referring back to FIG. 1, an optical pickup 2 emits a laser beam withwhich information recorded on the optical disc 10 is reproduced andreceives reflected light from the optical disc 10 to produce areproduction signal. When the optical disc 10 is loaded in the discplayer 1, the optical pickup 2 reads a TOC recorded in the lead-in area,which is provided at the most inner side of the optical disc 10. A motor3 for optical pickup movement (corresponding to an optical-pickup movingunit in the claims) moves the position where the optical pickup 2 emitsthe laser beam in the radial direction of the optical disc 10(hereinafter referred to as “moves the optical pickup 2”). A spindlemotor 4 rotates and drives the optical disc 10.

A radio-frequency (RF) amplifier 5 receives the reproduction signal andthe TOC from the optical pickup 2 to generate an RF signal. A digitalsignal processor (DSP) 6 receives the RF signal from the RF amplifier 5to binarize the RF signal as digital data and to perform errorcorrection for the binarized digital data. If the DSP 6 cannot performthe error correction for the digital data, the DSP 6 determines that theoptical pickup 2 cannot read the information recorded on the opticaldisc 10 because of a scratch on the optical disc 10 and outputs a readerror signal. The DSP 6 separates the digital data subjected to theerror correction into a digital audio signal and a synchronizationsignal and outputs the separated signals. The synchronization signalincludes the content of the TOC.

A controller 7 receives the synchronization signal and the read errorsignal from the DSP 6. The controller 7 performs tracking and focusingfor an actuator (not shown) of the optical pickup 2 based on thesynchronization signal received from the DSP 6. The controller 7 alsorotates and controls the spindle motor 4 based on the synchronizationsignal received from the DSP 6.

Furthermore, the controller 7 controls the motor 3 for optical pickupmovement based on the synchronization signal and the read error signalreceived from the DSP 6. When the controller 7 does not receive the readerror signal from the DSP 6, that is, when the optical pickup 2 can readthe information recorded on the optical disc 10, the motor 3 for opticalpickup movement moves the optical pickup 2 in the radial direction suchthat the optical pickup 2 follows the recording track on the opticaldisc 10.

When the controller 7 receives the read error signal from the DSP 6, thecontroller 7 controls the motor 3 for optical pickup movement to movethe optical pickup 2 toward the outer side of the optical disc 10 by apredetermined length of track jump. The predetermined length of trackjump indicates, for example, the radial distance of the optical disc 10when the controller 7 skips the information on the recording track bythe distance corresponding to a predetermined time, for example, threeto 10 seconds.

Before actually moving the optical pickup 2, the controller 7 determineswhether the music track that is being reproduced is different from themusic track to which the optical pickup 2 is to be moved (thedestination music track) and whether the optical pickup 2 is to be movedbeyond the head of the destination music track. If the controller 7determines that the music track that is being reproduced is differentfrom the destination music track and that the optical pickup 2 is to bemoved beyond the head of the destination music track, the controller 7controls the motor 3 for optical pickup movement to move the opticalpickup 2 to the head of the destination music track.

Specifically, after the optical disc 10 is loaded in the disc player 1,the controller 7 controls the motor 3 for optical pickup movement tomove the optical pickup 2 to the lead-in area of the optical disc 10.The optical pickup 2 reproduces the information in the lead-in area ofthe optical disc 10 to acquire the TOC. The acquired TOC is supplied tothe controller 7 through the RF amplifier 5 and the DSP 6.

The controller 7 acquires from the TOC the number of music tracks, themusic track numbers, the absolute time of the head of each music trackon the optical disc 10 loaded in the disc player 1.

When the optical pickup 2 reproduces the n−th (n denotes a integer ofone or more) music track, as shown in FIG. 4 a, the controller 7determines the absolute time of the position where the optical pickup 2is currently reproducing the information from the subcodes and so on.The controller 7 recognizes that a scratch is made on the optical disc10 from the read error signal received from the DSP 6.

When the controller 7 recognizes that the scratch is made on the opticaldisc 10, the controller 7 sets a destination of the optical pickup 2 tobe moved toward the outer side of the optical disc 10 by a predeterminedlength of track jump in order to avoid the scratch made on the opticaldisc 10, as shown in FIG. 4B. The controller 7, then, determines theabsolute time of the set destination of the optical pickup 2. Forexample, the absolute time of the set destination of the optical pickup2 is determined by adding the time corresponding to the predeterminedlength of track jump to the absolute time of the position where theoptical pickup 2 is currently reproducing the information.

The controller 7 refers to the acquired TOC and compares the absolutetime of the current reproduction position with the absolute time of thehead of each music track to determine the music track number (n−th musictrack) currently being reproduced. In addition, the controller 7compares the absolute time of the set destination of the optical pickup2 with the absolute time of the head of each music track to determinewhether the set destination of the optical pickup 2 is beyond the headof the music track number (n+1−th music track) subsequent to the musictrack number (n−th music track) currently being reproduced.

If the controller 7 determines that the set destination of the opticalpickup 2 is beyond the head of the n+1−th music track subsequent to then−th music track currently being reproduced, the controller 7 refers tothe TOC to determine the absolute time of the head of the n+1−th musictrack. The controller 7 controls the motor 3 for optical pickup movementto move the optical pickup 2 to the position corresponding to thedetermined absolute time (the head of the n+1−th music track), as shownin FIG. 4C.

Referring back again to FIG. 1, a digital-analog (D/A) converter 8receives the digital audio signal supplied from the DSP 6, converts thereceived digital audio signal into analog audio information, and outputsthe converted analog audio information.

The operation of the disc player 1 and a method of reproducinginformation on the optical disc 10 in the disc player 1, according tothe first embodiment, will now be described. FIG. 5 is a flowchartshowing the operation of the disc player 1 and the method of reproducinginformation on the optical disc 10 in the disc player 1, according tothe first embodiment. In Step S1, with the information on the opticaldisc 10 being reproduced in the disc player 1, the controller 7determines whether a read error signal is received from the DSP 6. Ifthe controller 7 determines that the read error signal is not receivedfrom the DSP 6 (the determination is negative in Step S1), then in StepS2, the controller 7 determines whether the reproduction of theinformation on the optical disc 10 terminates in the disc player 1.

If the controller 7 determines that the reproduction of the informationon the optical disc 10 terminates (the determination is affirmative inStep S2), the process ends. If the controller 7 determines that thereproduction of the information on the optical disc 10 does notterminate (the determination is negative in Step S2), the controller 7goes back to Step S1.

If the controller 7 determines that the read error signal is receivedfrom the DSP 6 (the determination is affirmative in Step S1), then inStep S3, the controller 7 sets a destination of the optical pickup 2 tobe moved toward the outer side of the optical disc 10 by a predeterminedlength of track jump.

In Step S4, the controller 7 determines whether the absolute time of theset destination of the optical pickup 2 is beyond the absolute time ofthe head of the subsequent music track. If the controller 7 determinesthat the absolute time of the set destination of the optical pickup 2 isnot beyond the absolute time of the head of the subsequent music track(the determination is negative in Step S4), then in Step S5, thecontroller 7 controls the motor 3 for optical pickup movement to movethe optical pickup 2 to the destination set in Step S3. The controller 7goes back to Step S1 while continuing the reproduction of theinformation on the optical disc 10.

If the controller 7 determines that the absolute time of the setdestination of the optical pickup 2 is beyond the absolute time of thehead of the subsequent music track (the determination is affirmative inStep S4), then in Step S6, the controller 7 determines whether theabsolute time of the set destination of the optical pickup 2 is beyondthe absolute time of the start position of the lead-out area. If thecontroller 7 determines that the absolute time of the set destination ofthe optical pickup 2 is beyond the absolute time of the start positionof the lead-out area (the determination is affirmative in Step S6), thenin Step S7, the controller 7 sets the destination of the optical pickup2 to the head of the first music track because the information in thelead-out area cannot be reproduced. In Step S5, the controller 7controls the motor 3 for optical pickup movement to move the opticalpickup 2 to the destination set in Step S7. The controller 7 goes backto Step S1 while continuing the reproduction of the information on theoptical disc 10.

If the controller 7 determines that the absolute time of the setdestination of the optical pickup 2 is not beyond the absolute time ofthe start position of the lead-out area (the determination is negativein Step S6), then in Step S8, the controller 7 sets the destination ofthe optical pickup 2 to the head of the subsequent music track. In StepS5, the controller 7 controls the motor 3 for optical pickup movement tomove the optical pickup 2 to the destination set in Step S8. Thecontroller 7 goes back to Step S1 while continuing the reproduction ofthe information on the optical disc 10.

As described above in detail, according to the first embodiment, whenthe controller 7 receives the read error signal, the controller 7 sets aposition where the optical pickup 2 reaches in a predetermined time anddetermines whether the set position is beyond the head of the musictrack subsequent to the music track being currently reproduced. If thecontroller 7 determines that the set position is beyond the head of thesubsequent music track, the controller 7 controls the motor 3 foroptical pickup movement to move the optical pickup 2 to the head of thesubsequent music track. Accordingly, when the optical pickup 2 is movedto the subsequent music track where the information on the optical disc10 is reproduced with a scratched portion being skipped, the informationis reproduced from the head of the subsequent music track. As a result,the entire music track having no scratch can be reproduced, thusallowing a user to comfortably listen to the music information even onthe disc having a scratch or the like.

According to the first embodiment, when the information on the opticaldisc 10 is reproduced with a scratched portion being skipped, thecontroller 7 determines whether the optical pickup 2 is to be movedbeyond the head of the subsequent music track without actually movingthe optical pickup 2. Accordingly, it is possible to reduce the load onthe motor 3 for optical pickup movement.

Second Embodiment

A second embodiment of the present invention will be described belowwith reference to the attached drawings. Since the entire structure of adisc player 1 according to the second embodiment is similar to that ofthe disc player 1 in FIG. 1, a detailed description is omitted herein.However, the disc player 1 according to the second embodiment operatesin a manner shown in FIGS. 6 and 7.

According to the second embodiment, when the controller 7 receives theread error signal from the DSP 6, the controller 7 controls the motor 3for optical pickup movement to actually move the optical pickup 2 towardthe outer side of the optical disc 10 by a predetermined length of trackjump.

Next, the controller 7 determines whether the music track to which theoptical pickup 2 is moved (the destination music track) is differentfrom the music track that was reproduced before the movement. If thecontroller 7 determines that the destination music track is differentfrom the music track that was reproduced before the movement, thecontroller 7 controls the motor 3 for optical pickup movement to movethe optical pickup 2 to the head of the music track subsequent to themusic track that was reproduced before the movement. The music trackdifferent from the music track that was reproduced before the movementcorresponds to the music track subsequent to the music track that wasreproduced before the movement.

Specifically, when the optical pickup 2 reproduces the n−th (n denotes ainteger of one or more) music track, as shown in FIG. 6 a, thecontroller 7 determines the absolute time of the position where theoptical pickup 2 currently reproducing the information and the musictrack number (the n−th music track) from the subcodes and so on. Thecontroller 7 recognizes that a scratch is made on the optical disc 10from the read error signal received from the DSP 6.

When the controller 7 recognizes that the scratch is made on the opticaldisc 10, the controller 7 controls the motor 3 for optical pickupmovement to move the optical pickup 2 toward the outer side of theoptical disc 10 by a predetermined length of track jump in order toavoid the scratch made on the optical disc 10, as shown in FIG. 6B. Thecontroller 7 then determines the absolute time and the music tracknumber of the destination from the subcodes and so on. The controller 7determines whether the music track to which the optical pickup 2 ismoved is different from the music track that was reproduced before themovement (whether the music track to which the optical pickup 2 is movedis the n+1−th music track). Since the controller 7 actually moves theoptical pickup 2, the controller 7 can read the subcodes.

If the controller 7 determines that the music track to which the opticalpickup 2 is moved (the n+1−th music track) is different from the musictrack that was reproduced before the movement (the n−th music track),the controller 7 controls the motor 3 for optical pickup movement tomove the optical pickup 2 to the head of the subsequent music track (then+1−th music track), as shown in FIG. 6C.

The operation of the disc player 1 and a method of reproducinginformation on the optical disc 10 in the disc player 1, according tothe second embodiment, will now be described. FIG. 7 is a flowchartshowing the operation of the disc player 1 and the method of reproducinginformation on the optical disc 10 in the disc player 1, according tothe second embodiment. In Step S11, with the information on the opticaldisc 10 being reproduced in the disc player 1, the controller 7determines whether a read error signal is received from the DSP 6.

If the controller 7 determines that the read error signal is notreceived from the DSP 6 (the determination is negative in Step S11),then in Step S12, the controller 7 determines whether the reproductionof the information on the optical disc 10 terminates in the disc player1.

If the controller 7 determines that the reproduction of the informationon the optical disc 10 terminates (the determination is affirmative inStep S12), the process ends. If the controller 7 determines that thereproduction of the information on the optical disc 10 does notterminate (the determination is negative in Step S12), the controller 7goes back to Step S11.

If the controller 7 determines that the read error signal is receivedfrom the DSP 6 (the determination is affirmative in Step S11), then inStep S13, the controller 7 controls the motor 3 for optical pickupmovement to move the optical pickup 2 toward the outer side of theoptical disc 10 by a predetermined length of track jump.

In Step S14, the controller 7 determines whether the music track thatwas reproduced before the movement is different from the music track towhich the optical pickup 2 is moved. If the controller 7 determines thatthe music track that was reproduced before the movement is the same asthe music track to which the optical pickup 2 is moved (thedetermination is negative in Step S14), the controller 7 goes back toStep S11 while continuing the reproduction of the information on theoptical disc 10.

If the controller 7 determines that the music track that was reproducedbefore the movement is different from the music track to which theoptical pickup 2 is moved (the determination is affirmative in StepS14), then in Step S15, the controller 7 sets the destination to thehead of the music track subsequent to the music track that wasreproduced before the movement. In Step S16, the controller 7 controlsthe motor 3 for optical pickup movement to move the optical pickup 2 tothe destination set in Step S15. The controller 7 goes back to Step S11while continuing the reproduction of the information on the optical disc10.

As described above in detail, according to the second embodiment, whenthe controller 7 receives the read error signal, the controller 7controls the motor 3 for optical pickup movement to move the opticalpickup 2 by the distance corresponding to a predetermined time. Thecontroller 7 determines whether the music track before the movement isdifferent from the destination music track. If the controller 7determines that the music track before the movement is different fromthe destination music track, the controller 7 controls the motor 3 foroptical pickup movement to move the optical pickup 2 to the head of themusic track subsequent to the music track before the movement.Accordingly, when the optical pickup 2 is moved to the subsequent musictrack where the information on the optical disc 10 is reproduced with ascratched portion being skipped, the information is reproduced from thehead of the subsequent music track. As a result, the entire music trackhaving no scratch can be reproduced, thus allowing the user tocomfortably listen to the music information.

According to the second embodiment, since the controller 7 actuallymoves the optical pickup 2 to determine whether the destination musictrack is different from the music track before the movement when theinformation on the optical disc 10 is reproduced with a scratchedportion being skipped, there is no need to perform a complicatedcalculation and, therefore, the load on the controller 7 can be reduced.

In addition, according to the second embodiment, since the subcodes areused to determine whether the destination music track is different fromthe music track before the movement, the optical pickup 2 can be movedeven if the lead-in area where the TOC is recorded on the optical disc10 has a scratch.

Although the optical pickup 2 is moved based on the absolute time of thehead of the music track set as the destination in the first and secondembodiments, the present invention is not limited to this case. Forexample, the P subcode, indicating the head of the music track, in thesubcodes may be used to move the optical pickup 2 to the head of thedestination music track. Alternatively, the Q subcode, indicating theelapsed time of the music track, in the subcodes may be used to move theoptical pickup 2 backward by the distance corresponding to the elapsedtime of the music track to cause the optical pickup 2 to reach the headof the destination music track.

Although the optical disc is used as the recording medium recording thecontent, and the content is the music information and a plurality ofblocks is music tracks in the first and second embodiments, the presentinvention is not limited to these cases. A magneto-optical disc (forexample, a minidisc (MD)) may be used as the recording medium recordingthe content. The content may be video information and the plurality ofblocks may be titles or chapters.

Although the controller 7 determines whether the destination music trackis beyond the head of the subsequent music track, when the opticalpickup 2 is moved by the distance corresponding to a predetermined time,to control the movement of the optical pickup 2 in the first embodiment,the present invention is not limited to this example. For example, whenthe controller 7 receives the read error signal in the reproduction ofthe n−th music track by the optical pickup 2, as shown in FIG. 8A, thecontroller 7 may determine whether the remaining reproduction time ofthe n−th music track is shorter than a predetermined time (for example,three to ten seconds). If the controller 7 determines that the remainingreproduction time of the n−th music track is shorter than thepredetermined time, the controller 7 controls the motor 3 for opticalpickup movement to move the optical pickup 2 to the head of the n+1−thmusic track, as shown in FIG. 8B.

Although the predetermined time is equal to the reproduction time (forexample, three to ten seconds) of the recording track, corresponding toa predetermined length of track jump, the present invention is notlimited to this meaning. For example, the predetermined time may belonger (for example, five to twelve seconds) than the reproduction timeof the recording track, corresponding to the predetermined length oftrack jump. In this case, if the remaining reproduction time of the n−thmusic track is slightly longer (for example, four to eleven seconds)than the reproduction time of the recording track, corresponding to thepredetermined length of track jump, the controller 7 determines that theremaining reproduction time of the n−th music track is shorter than thepredetermined time because the predetermined time is set so as to belonger than the remaining reproduction time of the n−th music track. Thecontroller 7 controls the motor 3 for optical pickup movement to movethe optical pickup 2 to the head of the n+1−th music track. The musicinformation is reproduced from the head of the n+1−th music trackwithout the n−th music track being incompletely reproduced, so that theuser can comfortably listen to the music information.

Although the music information is reproduced from the head of the firstmusic track when the set destination of the optical pickup 2 is beyondthe head of the lead-out area in the first embodiment, the presentinvention is not limited to this case. For example, the reproduction ofthe music information on the optical disc 10 may be terminated when theset destination of the optical pickup 2 is beyond the head of thelead-out area.

Although the optical pickup 2 is moved to the head of the music trackwhen the destination music track is different from the music trackbefore the movement in the first and second embodiments, an operationshown in FIGS. 8 ato 9D′ may be performed when a scratch is made at thehead of the destination music track. When a scratch on the optical disc10 is detected in the reproduction of the music information of the n−thmusic track, as shown in FIG. 8 a, the controller 7 controls the motor 3for optical pickup movement to move the optical pickup 2 by apredetermined length of track jump, as shown in FIG. 9B.

The controller 7 then determines whether the destination music track(the n+1−th music track) is different from the music track that wasreproduced before the movement (the n−th music track). If the controller7 determines that the destination music track is different from themusic track that was reproduced before the movement, the controller 7controls the motor 3 for optical pickup movement to move the opticalpickup 2 to the head of the n+1−th music track, as shown in FIG. 9C. Ifa scratch is made also at the head of the n+1−th music track, thecontroller 7 detects the scratch from the read error signal received. Inthis case, the controller 7 controls the motor 3 for optical pickupmovement to move the optical pickup 2 again by the predetermined lengthof track jump, as shown in FIG. 9D.

Since the n+1−th music track is significantly jumped from its head inthe example in FIG. 9D, the controller 7 may reproduce the musicinformation from the position (shown in FIG. 9B) to which the opticalpickup 2 is initially moved, as shown in FIG. 9D′.

Although the absolute time and the music track number of the destinationof the optical pickup 2 are determined from the subcodes in the secondembodiment, the present invention is not limited to this case. Forexample, the absolute time and the music track number of the destinationof the optical pickup 2 may be determined from the TOC recorded in thelead-in area. Alternatively, both the TOC and the subcodes are used todetermine the absolute time and the music track number of thedestination of the optical pickup 2, instead of using either the TOC orthe subcodes. Using both the TOC and the subcodes allows the opticalpickup 2 to be moved even when either the TOC or the subcodes cannot beread.

It will be further understood by those skilled in the art that theforegoing description is of the preferred embodiments of the presentinvention and that various changes and modifications may be made to theinvention without departing from the spirit and scope thereof.

The present invention is useful for a disc player uses an optical pickupto read information recorded on that is rotated and driven.

1. A disc player that reproduces information in a plurality of blockssequentially provided on a disc, the disc player comprising: an opticalpickup operable to read the information recorded on a first block of thedisc; a moving unit operable to move the optical pickup for apredetermined period of time when the optical pickup is no longer ableto read the information recorded on the first block; and a controlleroperable to direct the moving unit to move the optical pickup to thehead of a second block subsequent to the first block if the portion ofthe disc to which the optical pickup will reach after being moved forthe predetermined time is within the second block.
 2. The disc playeraccording to claim 1, wherein the controller is operable to determinethe position that the optical pickup will reach by being moved for thepredetermined time, and the controller is operable to control the movingunit to move the optical pickup directly to the head of the second blockif the position determined is beyond the head of the second block. 3.The disc player according to claim 2, wherein the controller is operableto determine whether the position that the optical pickup will reach bybeing moved for the predetermined time is beyond the head of the secondblock based upon a table of contents recorded on the disc.
 4. The discplayer according to claim 3, wherein the disc is a compact disc, and thefirst and second blocks are tracks on the compact disc.
 5. The discplayer according to claim 2, wherein the controller is operable todetermine whether the position that the optical pickup will reach bybeing moved for the predetermined time is beyond the head of the secondblock based upon subcodes recorded on the disc.
 6. The disc playeraccording to claim 1, wherein the controller is operable to control themoving unit to actually move the optical pickup by a distancecorresponding to a predetermined time when the optical pickup is notable to read the information recorded on the disc, and the controller isoperable to control the moving unit to subsequently move the opticalpickup to the head of the second block if the position to which theoptical pickup actually moved was beyond the head of the second block.7. The disc player according to claim 6, wherein the disc is a compactdisc, and the first and second blocks are tracks on the compact disc. 8.The disc player according to claim 1, wherein the controller is operableto acquire a remaining reproduction time of the first block when theoptical pickup is no longer able to read the information recorded on thefirst block of the disc, and the controller is operable to control themoving unit to move the optical pickup to the head of the second blockif the remaining reproduction time is less than the predetermined periodof time.
 9. The disc player according to claim 8, wherein the controlleris operable to acquire the remaining reproduction time of the firstblock based upon a table of contents recorded on the disc.
 10. The discplayer according to claim 9, wherein the disc is a compact disc, and thefirst and second blocks are tracks on the compact disc.
 11. The discplayer according to claim 8, wherein the controller is operable toacquire the remaining reproduction time of the first block based uponsubcodes recorded on the disc.
 12. A method of reproducing informationin a plurality of blocks sequentially provided on a disc, the methodcomprising: determining a position where an optical pickup will reach ina predetermined time when the optical pickup is not able to read theinformation recorded on a first block of the disc; determining whetherthe position is beyond the head of a second block subsequent to thefirst block; and moving the optical pickup to the head of the secondblock if it is determined that the position is beyond the head of thesecond block.
 13. The method according to claim 12, wherein thedetermination of whether the position is beyond the head of the secondblock subsequent to the first block is based upon a table of contentsrecorded on the disc.
 14. The method according to claim 13, wherein thedisc is a compact disc, and the first and second blocks are tracks onthe compact disc.
 15. The method according to claim 12, wherein thedetermination of whether the position is beyond the head of the secondblock subsequent to the first block is based upon subcodes recorded onthe disc.
 16. The method of claim 12, comprising moving the opticalpickup to the position before subsequently moving the optical pickup tothe head of the second block.
 17. A method of reproducing information ina plurality of blocks sequentially provided on a disc, the methodcomprising: moving an optical pickup by a distance corresponding to apredetermined time when the optical pickup is not able to read theinformation recorded on a unreadable portion of the disc; determiningwhether a block to which the optical pickup has been moved to includesthe unreadable portion of the disc; and moving the optical pickup to thehead of the block to which the optical pickup has been moved if it isdetermined that the block does not include the unreadable portion of thedisc.
 18. The method according to claim 17, wherein the optical pickupis moved by the distance corresponding to the predetermined time basedupon subcodes recorded on the disc.
 19. The method according to claim18, wherein the disc is a compact disc, and the block is a track on thecompact disc.
 20. The method according to claim 17, wherein the opticalpickup is moved by the distance corresponding to the predetermined timebased upon a table of contents recorded on the disc.